CVE-2021-34675

NEX Forms <= 7.8.7 - Authentication Bypass for PDF Reports

2021-06-11 00:00

Strategic Overview

Status: Patched in 7.8.8
Affected Plugin: nex-forms
Affected Version: <= 7.8.7
CVSS: 7.5High
Weakness type: CWE-287 · Improper Authentication
CVE: CVE-2021-34675

At a glance

CVE-2021-34675 is a high-severity Improper Authentication vulnerability in the nex-forms WordPress plugin, affecting versions <= 7.8.7. It carries a CVSS score of 7.5 (reachable over the network; low attack complexity; high confidentiality impact). Exploitation requires no authentication. The issue is fixed in version 7.8.8; sites on affected versions should update now. Disclosed June 2021, reported by rauschecker.

Vulnerability Overview

Basix NEX-Forms through 7.8.7 allows authentication bypass for stored PDF reports.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user. A successful exploit has high impact on confidentiality.

CWE-287: Improper Authentication

Reaching this weakness in nex-forms <= 7.8.7 takes a caller who can reach the endpoint. Improper authentication means the mechanism that proves who a caller is can be satisfied without the secret it was supposed to require.

An attacker authenticates as another user — administrators included — without ever knowing a password, so password policies and login rate limits never come into play. For nex-forms the fix is 7.8.8: builds <= 7.8.7 are affected, anything from 7.8.8 onward is not.

Remediation

Update to version 7.8.8, or a newer patched version

How does WordSec protect against this?

Because it turns on account access, WordSec's login security is the relevant layer: role-based two-factor, captcha and brute-force limits raise the cost of getting the account this needs. None of that substitutes for the fix: nex-forms 7.8.8 closes this, and updating the plugin is the step that ends it.

Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-34675 https://www.wordfence.com/threat-intel/vulnerabilities/id/f5c1f0f4-4557-4ae9-bf0d-14c61721a2c5 https://nvd.nist.gov/vuln/detail/CVE-2021-34675

CVSS Vector

7.5

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityNone
AvailabilityNone

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